Peripheral & CNS Degeneration & Regeneration

Question 1

What is the mechanism of TGF-B in neuronal degeneration and regeneration?

Answer 1

Neuroprotective

Question 2

What is transsynaptic (transneuronal) degeneration?

Answer 2

Degeneration of a neuron that either synapses upon or receives a synaptic signal

Question 3

Blockage of this receptor in the CNS promotes neuronal regeneration and plasticity in uninjured neurons.

Answer 3

Nogo-66 Receptor

Question 4

What are the primary functions of microfilaments, neurofilaments, and microtubules in neurons?

Answer 4

Microfilaments and microtubules are involved with neuronal function. Neurofilaments are more involved with structural support for the neuron.

Question 5

What is the function of Chondroitin Sulfate in neuronal regeneration and plasticity?

Answer 5

Chondroitin sulfate is produced by glial cells and supports the growth and development of new neurons. When surrounding mature neurons, however, chondroitin sulfate prevents regeneration and plasticity

Question 6

Where can Nissl bodies be found in the nervous system?

Answer 6

Within the soma and dendrites of neurons. Nissl is absent from the axon hillock and axon

Question 7

What is chronic axotomy?

Answer 7

Prolonged periods in which injured neurons remain without targets during axonal regeneration

Question 8

What is a neuroma?

Answer 8

Accumulation of axonal endings unconnected to another neuron

Question 9

This cytokine acts on neurons and glia to mediate ischemic, excitotoxic, and traumatic brain injury.

Answer 9

IL-1

Question 10

Stress, glucocorticoids, and granule cell stimulation have what effect on neurogenesis?

Answer 10

Inhibit neurogenesis

Question 11

What is excitotoxic degeneration?

Answer 11

Degeneration of neurons due to overexposure to excitatory signals

Question 12

What is chronic denervation?

Answer 12

A distal nerve stump is maintained by Schwann Cells, but is not reconnected to the proximal nerve

Question 13

Nissl substance is important for protein maintenance and neuronal processes. What types of neurons have a higher density of Nissl substance?

Answer 13

Motor neurons - require more proteins for functioning

Question 14

What is the most abundant Insulin-Like growth factor in the CNS?

Answer 14

IGF-2 found in highly myelinated tracks of the CNS

Question 15

What is the function of neurotrophins?

Answer 15

Stimulate proliferation, differentiation, survival, and regeneration of mature oligodendryocytes

Question 16

What components make up the cytoskeleton of the nerve cell?

Answer 16

Microfilaments (actin), neurofilaments (intermediate filaments), microtubules (tubulin)

Question 17

This cytokine contributes to neuronal injury.

Answer 17

TNF-a

Question 18

What describes the degeneration of the distal axon following the degeneration of the axon terminal?

Answer 18

Wallerian Degeneration

Question 19

What is the effect of the complement pathway on neurogenesis?

Answer 19

Local production of complement protects the healthy nerves and is needed for myelin clearance post-injury

Question 20

True/False. The number of neurofilaments inversely correlates to the diameter of the axon.

Answer 20

False. The number of neurofilaments is directly correlated with axon diameter. Motor neurons have a greater number of neurofilaments that sensory neurons.

Question 21

This term describes the degeneration of the axon terminal distal segment

Answer 21

Terminal degeneration

Question 22

NOS and NMDA receptor inhibitors promote survival of what structure?

Answer 22

Clark’s nucleus - proprioception

Question 23

What term describes the dispersal and redistribution of Nissl substance in a damaged neuron?

Answer 23

Chromatolysis

Question 24

These proteins guide PNS axonal regeneration through pathfinding, fasciculation, and blood vessel formation.

Answer 24

Neuropilins